Critical evaluation of modified-release formulation containing silybum marianum extract for oral application

Abstract

Silymarin is the extract of active ingredients of the plant Silybum marianum. It is used in medicine for curing or preventing liver and gall diseases for thousands of years. Silymarin has a low solubility and permeability, belongs to BCS class IV. Its current pharmacotherapy means conventional dosage forms such as capsules, but it results in low bioavailability. Our main goals through the research were to formulate matrix tablets with silymarin as active ingredient. We used different carbopols as matrix-forming polymers. The complexation of silymarin with different β-cyclodextrins was intended to increase the solubility of the active ingredient. By achieving sustained release, our aim was to offer a better alternative than the conventional unsuccessful oral therapy. Comparing the results of our research, we could select the carbopol-cyclodextrin combination with the optimal drug release from the twenty different compounds. With these compositions, more than 85% of the silymarin was dissolved. The cytocompatibility of our product was proven, and the technology provided much better bioavailability than the conventional silymarin therapy.